The very first teaser trailer for BioShock 2 has been included with the PS3 version. The footage is unlocked after completing BioShock on PS3, and shows a 11 year old girl (presumably a Little Sister) standing on the Atlantic Coast peering out into the ocean.

A cuddly Big Daddy toy dangles from her hand as the camera zooms out to show a cityscape bursting from the sand behind her.

Eventually the BioShock 2 logo fades in before the subtitle Sea of Dreams is written underneath. Guess this means it is confirmed for both PS3 and Xbox 360 in 2010.

Source: BioShock 2: Sea of Dreams Trailer